flintware

from The Century Dictionary.

• noun In ceramics: Pottery distinguished by the use of ground flints mixed with the clay.
• noun Pottery having a slip into which ground flints enter for a considerable part of its volume.

from the GNU version of the Collaborative International Dictionary of English.

• noun A superior kind of earthenware into whose composition flint enters largely.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A superior kind of earthenware made with flint.